This depends on a number of factor. If it was on an EVM chain with smart contract functionality, I'd suggest using the "pull over push" principle where you just provide a mechanism for users to claim the tokens rather than directly trying to push it to users. This way, the cost (gas/tx fee) is pushed over to the user.

That's the best approach I've seen across the board. If you go ahead with something else and as long as it gets the job done, do share.